In recent years, three-dimensional hybrid perovskites (CH₃NH₃PbX₃) with X = Cl, Br and I, due to their simple production methods and encouraging energy conversion efficiency in perovskite-based solar cells, have raised great attention. One of the main limitations in the development and application of these structures is the toxicity of lead. Investigation of the magnetic and optical properties including linear and nonlinear properties of lead-free organic–inorganic perovskites seems to be necessary. The main focus of this work is the iron substitutions at the lead site. Three-dimensional CH₃NH₃FeCl₃ organic–inorganic perovskite and two-dimensional hybrids, (CH₃(CH₂)₃NH₃)₂FeCl₄ and (C₆H₅(CH₂)₂NH₃)₂FeCl₄, were prepared. Firstly, we describe the synthesis method, crystal structure and magnetic behavior of the iron-based lead-free perovskites. Optical properties including linear and nonlinear behavior of the iron halide perovskites are also investigated. The results indicate the presence of iron oxide phase between the layers of (PEA)₂FeCl₄ perovskite structure and a superparamagnetic behavior with weak magnetization. Through the Z-scan approach, we observed high nonlinear optical response and high nonlinear refraction. The organic cation effect on the nonlinear absorption and nonlinear refraction is studied experimentally. The remarkable third-order nonlinear thermo-optical properties of quasi-2D/3D iron-based lead-free perovskites suggest the potential of these materials for photonics applications.

近年来，X = Cl、Br和I的三维杂化钙钛矿（CH ₃ NH ₃ PbX ₃）由于其制备方法简单且在钙钛矿基太阳能电池中具有令人鼓舞的能量转换效率而受到广泛关注。这些结构的开发和应用的主要限制之一是铅的毒性。研究无铅有机-无机钙钛矿的磁性和光学特性，包括线性和非线性特性似乎是必要的。这项工作的主要重点是铅位点的铁替代。三维 CH ₃ NH ₃ FeCl ₃有机-无机钙钛矿和二维杂化物，（CH ₃制备(CH ₂ ) ₃ NH ₃ ) ₂ FeCl ₄和(C ₆ H ₅ (CH ₂ ) ₂ NH ₃ ) ₂ FeCl ₄。首先，我们描述了铁基无铅钙钛矿的合成方法、晶体结构和磁性能。还研究了卤化铁钙钛矿的光学特性，包括线性和非线性行为。结果表明，(PEA) ₂ FeCl ₄钙钛矿结构层之间存在氧化铁相，并且具有弱磁化的超顺磁性行为。通过Z扫描方法，我们观察到高非线性光学响应和高非线性折射。实验研究了有机阳离子对非线性吸收和非线性折射的影响。准 2D/3D 铁基无铅钙钛矿显着的三阶非线性热光特性表明这些材料具有光子学应用的潜力。